Saint Louis University proposes to evaluate acellular Bordetella pertussis vaccines, conjugated Haemophilus influenza type b and other bacterial vaccines, live attenuated influenza A and B virus vaccines, live attenuated parainfluenza virus vaccines, rotavirus vaccines and other vaccines such as herpes vaccines and hepatitis A vaccines as they become available. Sample protocols have been previously submitted and these are designed to illustrate our approach to testing vaccines of different types including vaccinia vector vaccines. The protocols summarize our plans to develop independent and collaborative protocols and work closely with other vaccine centers, the NIAID, and industry in evaluating vaccines for use in the general population. We propose to conduct clinical evaluation of investigational vaccines, and in addition we propose to develop new candidate vaccines such as parainfluenza virus vaccines and evaluation of antiviral compounds and other measures of controlling infections. We propose to study the epidemiology of viral infections including the subtype epidemiology of respiratory syncytial virus; vaccine studies in the elderly are proposed. This vaccine center will retain its major focus on evaluating vaccines in infants and children; however, we do have the experience and populations to evaluate vaccines in young adults and the elderly including studies in an isolation unit.